The overall purpose of the proposed project is to determine the cost-effectiveness, the acceptability and commercial applications of an interactive computer-mediated smoking cessation program delivered on-line through an established international computer network. The intent is to make readily available an inexpensive, effective smoking cessation program to the growing numbers of individuals and groups who have access to personal computers at home, schools, hospitals and at work. It is anticipated that Phase I results will prove the cost-effective and client-acceptability information necessary to pursue the research and development into Phase II. Positive results in Phase I would dictate broader trials in a variety of settings such as hospitals, schools, group practices and corporations in Phase II. Successful results in Phases I and II would have important implications for the feasibility of providing both commercial and non-commercial clinical and human services through computer networks on an international scale.